The invention relates to a galvanizing device having at least one jet cell through which a work piece to be galvanized, for example, a brake line or similar, is conducted, having a contact zone located after the jet cell in the direction of transportation and at least one partition separating the jet cell from the contact zone and a seal surrounding the work piece which is located between the partition and the jet cell.
In the galvanizing process, electrically conductive liquids (electrolytes) are used in which the work pieces are immersed and in which the work pieces are covered with a metal coating. Aqueous, acidic or alkaline solutions are employed as electrolytes. The anodes consist mostly of the metal to be precipitated. A zinc electrolyte is employed in the zinc coating of metal, for example. The work piece is immersed in the electrolyte and attached to the negative pole (cathode) of a direct current supply. A soluble zinc anode (positive pole) is immersed in the bath at the same time. Under the effects of the direct current, the split salt molecules separate, depending on their charge. The positive zinc ions migrate to the negative pole, i.e., the work piece, and are deposited thereon. The coating is created on the work piece through reduction (electron absorption) of the positive zinc ions. At the same time, the anode gives off zinc ions to the solution, whereby the anode slowly dissolves. The negative ions give off their charge at the anode.
Not only metallic (conductive) work pieces can be coated in this way, but also plastics. For this they are chemically metallized, i.e., made conductive. The range of uses is wide: household objects, sanitary articles or motor vehicle components, for example, brake lines, can be coated.
Brake lines, for example, are zinc-coated in a galvanizing device with high-speed zinc deposition. Jet cells, in which the galvanizing process takes place, are now used as the core of the device. The tube to be galvanized is passed through these jet cells. In addition, zinc electrolyte is pumped through these jet cells at high pressure. A contact zone, by means of which electrical contact is made with the tube, is located between each jet cell section, separated by one or two partitions. The contacts are cooled by means of a coolant circuit. This coolant circuit must be kept separate from the zinc electrolyte circuit. The seal for this is provided between the jet cells and the contact zone by means of plastic stripper plates. These plates are placed over the tubes so that the tube passes through the plates, whereby the electrolyte adhering to the outside of the tube is stripped off. It has turned out to be disadvantageous that the stripper plate touches continuously along the surface of the tube, causing wear on the stripper plate and permanently enlarging the opening through which the tube passes, so that the seal can no longer be guaranteed after a short time.
It is therefore the object of the invention to prepare a galvanizing device in which less electrolyte is entrained and in which the service life of the seal is longer.